JP2006516372A - Video network - Google Patents

Abstract

The video network has a plurality of video sources that provide high-resolution video data and low-resolution video data having a lower resolution than the high-resolution video data to the network, and at least one that processes the video data received via the network. One destination device, a network switch for selectively routing data from the video source to the destination device, and a low resolution representation from a subset of at least a plurality of video sources connected to the network switch. A network controller having a graphical user interface (GUI) for displaying on a display device together with identification information for associating video data with each video source, and a video source for high resolution video data using the graphical user interface And a user selection means for corresponding the destination device user to select, from a video source is selected, and control means for controlling the routing of high-resolution video data to the selected destination device.

Description

  The present invention relates to a video network and a video network control apparatus.

  2. Description of the Related Art In a studio, a technique for connecting a plurality of video / audio devices to each other using a switching device, which is often a cross point switch, is known. We have a need for a system that links audio and video equipment in a studio by a switched local area network such as Ethernet (registered trademark) that operates with a well-known protocol such as the Internet Protocol (IP). I found sex.

  Audio and video equipment used in the studio includes, for example, a camera, an editor, an audio mixer, a video tape recorder (VTR), and the like. Some devices both receive and generate audio and video data, and some devices require control data to control the device. For example, the VTR requires control data for controlling functions such as playback, stop, pause, and jog.

  A video network according to the present invention processes a plurality of video sources for sending high-resolution video data and low-resolution video data having a lower resolution than the high-resolution video data to the network, and video data received via the network. At least one destination device, a network switch for selectively routing data from the video source to the destination device, and a network control device connected to the network switch, the network control device comprising: a display device; and at least a plurality of A graphical user interface (GUI) for displaying low resolution video data from a subset of video sources on a display device, together with identifying information that associates the low resolution video data with each video source, and a graphical user interface User selection means for the user to select a video source of high-resolution video data and a corresponding destination device, and control of routing of the high-resolution video data from the selected video source to the selected destination device Control means.

  The GUI allows one or more designated video sources to be linked to at least one destination device and low-resolution video data, referred to herein as “proxy” video, so that one or more videos The video data of the video source can be previewed before the source video data is selected and connected to at least one destination device.

  The display device preferably displays a plurality of display areas each displaying low resolution video data from a respective video source with associated identification information.

  The graphical user interface preferably provides one or more user operable switches identified by identifying information that selects a destination device connected to the selected video source.

  The network control device may include a user input device (for example, a mouse, a trackball, a tablet, etc.) for selecting a display screen region, and the switch that can be operated by the user is a display screen region that can be selected by the user input device. It may be.

  In order to avoid providing a separate user operator, the preferred display screen is a display screen with a touch sensor, and the switch that can be operated by the user is preferably a display screen area that can be selected by touching the user. .

  As a modified example, the network control apparatus may include a plurality of buttons that can be operated by the user corresponding to the video source and / or destination device to be selected.

  As a further variation, the graphical user interface provides at least one selection display area and allows the video source to be dragged and dropped into the selection display area corresponding to the video source to be connected to the destination device. It may be selected.

  The network is preferably a packet-based network in which video sources are associated with different multicast groups. In order to route low resolution video data and high resolution video data separately, each video source is associated with high resolution video data from the video source and the other is low resolution video data from the video source. Are preferably associated with at least two multicast groups associated with. Routing may be accomplished by the network controller by sending a message to the destination device so that the destination device joins the selected source multicast group.

  The video network may include a plurality of destination devices such as a video switching device and a display device. Examples of the video source include a video tape recorder and a video camera.

  The video network control device according to the present invention receives a high-resolution video data and a low-resolution video data having a lower resolution than the high-resolution video data via a network and a plurality of video sources that transmit the video data to the network. A video network controller used in a video network comprising at least one destination device for processing video data and a network switch connected to the video network controller and selectively routing data from the video source to the destination device. A graphical user interface (GUI) for displaying low resolution video data from a subset of at least a plurality of video sources on a display device with identification information associating the low resolution video data with each video source; A user selection means for a user to select a video source of high-resolution video data and a corresponding destination device using a local user interface, and a high-resolution video from the selected video source to the selected destination device. Control means for controlling routing of data.

  Further, the operation method of the video network control apparatus according to the present invention includes a plurality of video sources that transmit high-resolution video data and low-resolution video data having a lower resolution than the high-resolution video data to the network, and the network. A video network controller in a video network comprising: at least one destination device for processing received video data; and a network switch connected to the video network controller and selectively routing data from the video source to the destination device A method of operation comprising displaying low resolution video data from a subset of at least a plurality of video sources on a display device with identifying information associating the low resolution video data with each video source; and high resolution video data Video So Providing a user option to scan and corresponding destination device user to select, from a video source is selected, and a step of controlling the routing of high-resolution video data to the selected destination device.

  These and other aspects of the invention are defined in the appended claims.

Overview and Terminology In the embodiment shown in FIG. 1, the network is installed, for example, in a studio. This network includes a plurality of audio / visual (hereinafter referred to as AV) devices that are source groups, and these AV devices include three cameras S1 to S3 and three video tape recorders ( video tape recorder (hereinafter referred to as VTR) S4 to S6, two digital signal processors (hereinafter referred to as DSP) S7 and S8, and other source groups that generate only serial digital audio data It consists of S9 and S10. Further, the network includes a destination group AV device, and these AV devices include a video switch D8, a pair of monitors D2, a pair of audio processors D3, and a video processor D9. The Ethernet switch 2 connects between the source group AV device and the destination group AV device. The AV devices S1 to S10 and D1, D2, D3, D8, and D9 of these groups are all connected to at least one of the enhanced network interface cards (hereinafter referred to as ENIC) NI1 to NI11. Has been. The ENIC is an extension of the configuration and functions of the standard network interface card, and details thereof will be described later using the ENIC_AIR 750. The network further comprises a first switching / routing client 6, a further switching / routing client 61 and a network manager 4. A user may change the current configuration of virtual circuit-switched connections in a network through a graphical user interface (GUI) generated by a computer software application. Can be requested. The GUI is displayed on the monitor associated with the exchange / routing client 6 in this embodiment. As another example, the GUI may be displayed on a monitor related to the network manager 4. This GUI will be described in detail later with reference to FIGS.

  This network is an Ethernet multicast network including an Ethernet switch 2, and the Ethernet switch 2 is an asynchronous n-Gigabit Ethernet switch in which n is 1 to 10. To this Ethernet switch 2, source “group” AV devices S1 to S0, destination “group” AV devices D1, D2, D3, D8, and D9, and a network control device are connected as network nodes. In this embodiment, the network control device is the network manager 4 and the exchange / routing clients 6 and 61.

  A source group is defined as an AV device that can generate or supply audio and / or video data to be transmitted over a network, such as a camera S1 or VTRS4. The source group AV device includes one or more input terminals and / or one or more output terminals. The input / output terminal of the AV device is connected to one port of ENIC NI1 to NI11. Different terminals of the same AV device may be connected to different ENICS. For example, in the specific example shown in FIG. 1, the first output terminal of the camera S1 of the source group is connected to the ENIC NI1, and the second Are connected to ENIC NI2. A destination group is defined as a device that receives packet audio and / or video data and processes received data via a network, such as a video switch D8, a video processor D9, or an audio processor D3. The destination group, like the source group, comprises one or more input terminals and / or one or more output terminals, which may be connected to different ports of the same ENIC, each port of a different ENIC. You may connect to.

  In the case of data exchange in the network (data exchange event), the destination group can function as a source group, and the source group can also function as a destination group. For example, the VTRS 4 has audio, video, status, proxy sources and / or destination devices associated with them, and in the case of data exchange, from the video source device on the VTRS 4 via the network. Thus, the VTRS 4 functions as a source group. In the case of different data exchange, the VTRS 4 receives and records data from the camera S1 via the video processor D9 via the network. In this case, the processed video data is received from the network by the destination device (ENIC input port) related to VTRS 4 and then supplied to VTRS 4 in a serial digital format for recording. Thus, in this context, VTRS 4 functions as a destination group.

  Here, for AV equipment, the source groups are shown as S1 to S10, the destination groups are shown as D1, D2, D3, D8, and D9, and each equipment in these groups is connected to one or more ENIC ports. The ENIC ports are represented as “source device” and “destination device”. The “source device” is defined as an ENIC output port that outputs packet data to the network or serial digital data to the AV device of the destination group. The “destination device” receives packet data from the network or serially. It is defined as an ENIC input port that receives digital data from the output terminal of the source group AV device. The source device and destination device of ENIC can be related to the source group (AV device), can receive data transmitted from the source group through the network, or can be related to the destination group, and can receive data from the network. To the destination group. The network manager 4 monitors the mapping between the ENIC port and the AV device.

  The network manager 4 stores an alphanumeric label called “tally text” that is freely assigned to each device S1-S10 in the source group of the network. Specific examples of the collation text include, for example, the name “VTR1” given to the device S4 in the source group, the name of the photographer “Jim” given to the camera S1 in the source group, and the like. The collation text is recorded in the network manager 4. Names can be assigned in this way to all groups connected to the network. A label derived from the related source group AV device or destination group AV device can be attached to the source device and destination device of ENIC. Each source group AV device S1 to S6 and each destination group AV device D1, D2, D3, D8, D9 are connected to the Ethernet switch 2 via at least one network interface card NI1 to NI11 in order to connect to the network. Has been. These network interface cards NI1 to NI11 are specially adapted for transmitting audio and / or video data over a network based on the technology of the present invention and are called ENIC (Extended Network Interface Card). . One source group device or destination group device may be connected to a plurality of ENICs. For example, in the embodiment shown in FIG. 1, the camera source group device S1 is connected to NI1 and NI2 which are different ENICs. . In particular, one set of source device (output port) and destination device (input port) of the source group is connected to the first ENIC NI1, and the other set is connected to the second ENIC NI2. Each of the ENIC NI1 to NI8 includes a plurality of ports. The input ports of the first set of ENICs NI1 to NI7 receive data directly from source group devices such as cameras S1 to S3, VTRS4 to S6, DSPS7, S8, etc., and these ENIC output ports send packet data to the network. Output. On the other hand, the input ports of the second ENIC set NI8 to NI11 receive packet data originating from the other source group via the network, and the output ports of these ENICs are the video switch D8, the audio processor D3, etc. Serial digital audio and / or video data is supplied to the destination group device. This network may have a master ENIC NIM 63 (see FIG. 1), which will be described in detail in a later section on Frame Start Alignment.

  In a conventional studio, for example, a source group device such as a camera and a destination group device such as a video processor are connected via a crosspoint switch. In the conventional crosspoint switch, in order to securely connect each device via the crosspoint switch, it is necessary to connect a corresponding specific known device to a specific known port on the switch. On the other hand, the network shown in FIG. 1 includes an Ethernet switch 2 and is a virtual circuit switched connection that emulates a crosspoint switch in that at least one source group device can be connected to any one or more destination group devices. Configured by the network manager 4 and the exchange / routing client 6 to provide (virtual circuit-switched connections). The virtual circuit switched connection is realized by an Internet Protocol (IP) multicast network using the Internet Group Management Protocol (hereinafter referred to as IGMP) which is a well-known protocol, as shown in FIG. Is done. In a multicast network, data can be transmitted from one source device to a plurality of destination devices belonging to a predetermined multicast group via the network, and the multicast group to which the source device or destination device belongs is determined by IGMP. Can be identified. Each source device and destination device is assigned an identifier, and a predetermined multicast device is associated with a predetermined source device identifier and a predetermined destination device identifier, thereby defining a virtual connection. In the network shown in FIG. 1, unlike the conventional cross-switch network, the connection is flexibly set using the identifier and the multicast address and the related communication protocol. Which physical port to connect to can be freely selected.

  In the configuration shown in FIG. 1, the network operates as follows. That is, a single source device needs to belong to only one multicast group that is not shared by other source devices. At least one destination device joins the multicast group of the source device and receives data from the source device. The destination device joins the multicast group by issuing a multicast group join message and receives data from the associated source device. The network control devices 4, 6, 61 send a request to the Ethernet switch 2 for the device to join the multicast group of the appropriate source device to the destination device (that is, one input terminal of the destination group AV device or the corresponding ENIC port). Each virtual circuit switched connection is started by sending a control message instructing A plurality of destination devices can participate in a predetermined multicast group, and the Ethernet switch 2 performs a predetermined replication process on the data from the source device and transmits the replicated data to the multicast group. Data transmitted from the source device to a plurality of destination devices in the multicast group may be video data, audio data, time code data, status data, and the like.

Overview of ENIC The function of ENIC will be described in detail with reference to FIG. With ENIC, all devices in the source group such as cameras and all devices in the destination group such as VTRs that are not designed for the multicast network can be used in the multicast network. An ENIC is a “single dumb” device that can request to supply and receive streams of audio, video and control data. The ENIC cannot examine the network configuration and suggest changes to the configuration. Which multicast groups a given ENIC joins is controlled by the network manager 4, which instructs the ENIC to send a request to join these multicast groups to the Ethernet switch 2. In the configuration shown in FIG. 1, ENIC NI1 to NI11 are entities that are independent from the AV devices of the source group and destination group to which ENIC NI1 to NI11 are associated. It may be incorporated.

  Each ENIC has an Ethernet address and an IP address. The Ethernet address is indicated by a 48-bit value that identifies a physical address in the LAN, and the IP address (in IP version 4) is a 32-bit value that identifies the sending or receiving side of information in units of packets via the Internet. Indicated by value. The Ethernet address is often different from the IP address, but these two addresses can be made to correspond to each other using, for example, an Address Resolution Protocol (hereinafter referred to as ARP). The IP address is information necessary for the Ethernet switch 2 to route data to or from the ENIC. Each data stream associated with an ENIC is identified using both a multicast address and a user datagram protocol (UDP) port number. UDP is a transport layer protocol that mediates data communication over a network together with IP. UDP provides a port number to distinguish between different transaction requests (this service is not provided by IP). In this embodiment, each ENIC is associated with a unique IP address. As another example, a plurality of IP addresses may be associated with a single ENIC. In addition to the Ethernet address and the IP address, the ENIC is assigned an ENIC identifier (ID) and a plurality of port IDs corresponding to each of the destination device and the source device connected to the ENIC. All addresses and IDs associated with each ENIC are recorded in the network manager 4. The source device and the destination device (that is, individual input terminals and output terminals of the network node devices S1 to S8 and D1, D2, D3, D8, and D9) are one or more physical input ports and physical output ports of the ENIC. Corresponds to one port. The ENIC functions as a switch for switching data received from the Ethernet switch 2 to a designated physical output port and switching data from a designated physical input port to the Ethernet switch 2.

  A network realized using the Ethernet switch 2 is an asynchronous network. However, video data and audio data require synchronization processing. ENIC provides synchronization operations over the network and adjusts the position of the frames of different video streams, for example for editing purposes. Video and audio devices (that is, source group devices and destination group devices) connected to a network are, for example, serial digital interfaces (hereinafter referred to as SDI) that are digital standards for interface of component digital video. ) Or audio engineering society (hereinafter referred to as AES) digital audio standard for processing audio data. The ENIC converts data from the source device from the SDI or AES serial digital format on the transmission side to a packet format suitable for transmission via the network, specifically, a multicast UDP / IP data packet. On the receiving side, the ENIC converts the multicast UDP / IP data packet received from the network into a serial digital format suitable for delivery to the destination device. As a further function provided by ENIC, ENIC generates a video stream with reduced resolution called “proxy video” from a full resolution video stream. Proxy video is a bandwidth-reduced version of full resolution video information and information content for processing and / or downloading over a network client with limited memory capacity and / or processing power Suitable for use as a preview.

Network Manager Overview The network manager 4 cooperates with the exchange / routing clients 6, 61 to configure a network controller, which assigns multicast group identifiers to audio and video source devices and to destination devices. On the other hand, it is possible to instruct the Ethernet switch 2 to send a request to join a specific multicast group in order to receive data from the corresponding source device. The network manager 4 maintains information on the current state of the network and instructions for starting a change in device configuration or network connection issued from the network manager 4. In the configuration shown in FIG. 1, the network manager 4 is a personal computer (hereinafter referred to as a PC) connected to the network via a standard network interface card. As another configuration, the network manager 4 may be a workstation, for example, and the network control device may include two or more network managers.

  The network manager 4 maintains and manages a database that identifies the network configuration. In the configuration shown in FIG. 1, the database is stored in the PC that is the main body of the network manager 4. However, as another configuration, the database may be stored in at least one different PC. The database includes, for each ENIC, information such as the related Ethernet address, IP address, ENIC identifier, and source device and destination device (input port and output port of the network node device) currently connected to the ENIC via the network. Is stored. In the chapter “Network Configuration Data” to be described later, four different categories of devices for which the network manager 4 stores configuration data will be described. Further, the network manager 4 allocates network resources to the exchange / routing clients 6 and 61 and the ENIC NI1 to NI11, and instructs the destination device to transmit a request for joining a specific multicast group to the Ethernet switch 2. Thus, the function of changing the audio and / or video virtual circuit switching connection over the network and ensuring that the network is correctly connected from the viewpoint of each switching / routing client 6, 61 is provided. Yes.

The network configuration data network manager 4 stores and maintains a data set relating to each of devices belonging to a plurality of different categories on the network. Since the control message is supplied from the network manager 4 to the ENIC NI1 to NI11 (not the input port / output port), the ENIC port is classified as belonging to one of a plurality of device types / categories. The “source device” and “destination device” have already been described above.

  Specifically, the network configuration data has four basic types related to four different types of devices (ENIC input / output ports) and a fifth type related to a group of commonly controlled devices.

The four basic types are as follows.
1. SOURCE device: Video data, audio data and status data from the source device are properly formatted by the ENIC and sent to the multicast group on the network. Each source device can also send a video proxy with reduced bandwidth.
2. Destination device: DESTINATION device: Video data, audio data, and status data from the network are supplied to the destination device participating in the multicast group.
3. Control source device (CONTROL SOURCE device): A control command is generated by an ENIC or network client and unicast to a predetermined control destination device.
4). Control destination device (CONTROL DESTINATION): Receives a unicast control command from the control source device.

  The exchange / routing client 6 cannot directly access the source device and the control destination device. These devices are members of a CONTROL SOURCE GROUP that cannot be individually controlled. For example, the standard SDI video output and the super SDI output from the VTR are both supplied to the ENIC and transmitted to the Ethernet switch 2. In the network configuration, the SDI input is as four source devices including two video source devices V0 and V1 (corresponding to a signal from the SDI output and a signal from the super SDI output, respectively) and two audio sources A0 and A1. expressed. The four source devices are generated by the same physical device (source group is VTR). The four source devices have a common time code and stream status, ie, stop, fast forward (FF), rewind (rew), etc. Therefore, these four source devices are not individually controlled but collectively controlled by the control source group.

  In addition to the ENIC data structure to be described later, the network manager 4 associates with each of the above four device types, that is, a source group, a destination group, a control source group, and a control destination group. Save.

  For the source device, the network manager 4 stores the following data. That is, in these data, the upper 16 bits specify the ENICID, the lower 16 bits specify the UDP port ID, and the 8-bit value that specifies the data type (audio data, video data, status data). A 32-bit value that identifies the control source group to which the source device belongs, a first 32-bit multicast IP that identifies the destination device to which the source device transmits data, and a second that identifies the destination device to which the video proxy is transmitted. 32-bit multicast IP address, 64-byte collation text information, and a 32-bit “link” value that identifies the destination device ID associated with the destination device supplying the given source (the linked source is the network To other network devices after receiving data via As a source, it is supplied by a destination device (for example, chroma keyer) that outputs processed data to a network.) For a video source, a 32-bit value that specifies the number of video lines that delay transmission, and a source device An 8-bit status value indicating whether or not data can be transmitted via the network is included.

  For the destination device, the network manager 4 stores the following data. That is, in these data, the upper 16 bits specify the ENICID, the lower 16 bits specify the UDP port ID, and the 8-bit value that specifies the data type (audio data, video data, status data). A 32-bit value that identifies the IP address of the ENIC that realizes the destination device, a 32-bit MAST SRC IP that identifies the multicast IP address at which the destination device receives data, and the multicast IP address to which the destination device is assigned. A 32-bit value that identifies the source device that sends the data, an 8-bit collation text index, and a 32-bit value that identifies the source device ID associated with the source device to which the data is supplied by the destination device (the linked destination device is , One of the equipment that supplies the source When a 32-bit delay value specifying the number of video lines to delay the reproduction, if the destination device is in the on-air, or is in off-air, includes an 8-bit state value specifying the like or are controlled.

  For the control source device, the network manager 4 stores the following data. That is, in these data, the upper 16 bits specify the ENICID, the lower 16 bits specify the UDP port ID, the 32-bit value that specifies the ID of the control destination device to which the message is to be transmitted, The ENIC 32-bit IP address and 16-bit UDP port address that realize the specified control destination device and the ENIC 32-bit IP address and 16-bit UDP port address that realize the actual control source device are included.

  For the control destination device, the network manager 4 stores the following data. In these data, the upper 16 bits specify the ENICID, the lower 16 bits specify the UDP port ID, the 32-bit ID of the control source group to which the specified control destination device belongs, and the control destination device The 32-bit ID of the control source to which the control source is connected, the 32-bit IP address and 16-bit UDP port address of the ENIC that realizes the related control source device, and the 32-bit IP address of the ENIC that realizes the specified control destination device 16-bit UDP port address is included.

  For the control source group (a predetermined source and control destination device are associated), the network manager 4 stores the following data. That is, in these data, the upper 16 bits specify the ENICID, the lower 16 bits specify the UDP port ID, the 16-bit value specifying the number of devices belonging to the source group, and the group Sends status data to each of the 32-bit value that identifies the IDs (up to 10) of all the devices to which it belongs, the 32-bit value that identifies the control destination device associated with the group, and the devices (up to 10) in the group A 32-bit source status value that identifies the status source device to be used, 64 bytes containing collation text for all devices in the group, 128 bytes of description data indicating up to 10 descriptions for the group, and 64 bytes of control Source name and 9-bit state value are included.

  The network manager 4 stores the following data as the ENIC data structure for the ENIC NI1 to NI11 in addition to the five categories of the data set described above. That is, these data include a 16-bit ID that uniquely identifies the ENIC, a 48-bit media access control (MAC) address associated with the ENIC, and an IP address of the 32-bit ENIC. , A 32-bit IP address of the ENIC master clock and a 32-bit field that specifies the number of parameters used in hardware mapping of the device.

  The ENIC data structure includes all the hardware constraints that map the four source devices in the above example to the physical ports of the ENIC card and limit the ideal model described above. When ENIC is initialized, ENIC receives information about what devices are connected to its UDP (RS422) in order to be able to use the correct driver.

  Thus, the network manager 4 stores, for each destination group device, the multicast ID address MAST SRC IP from which the destination group guides data. Note that different input / output ports of a given destination group can receive data from different IP multicast groups. The received data depends on the ENIC port (ie, source / destination device) to which the input / output port of the destination group (AV device) is connected. As described above in relation to the destination data structure, for each destination group, the ID for both the destination group itself and the source group that supplies the data is stored in the network configuration database. The source / destination group ID includes an identifier of the ENIC that connects the source / destination group to the network and an identifier of the ENIC port to which the related source / destination group is connected. A similar set of information is stored for each source group.

Overview of Switching / Routing Client 6 In the configuration shown in FIG. 1, the switching / routing client 6 is realized by a PC connected to a network via a standard network interface card, like the network manager 4. The switching / routing client 6 can examine and / or change the configuration of the network, i.e. change the virtual circuit switched connection between the source device and the destination device. Such a change can be performed by the user operating a GUI which will be described later with reference to FIGS. In the configuration shown in FIG. 1, the exchange / routing client 6 controls both the video switch D8 and the associated ENIC NI8 and controls the supply of video data from the ENIC NI8 to the network and from the network to the ENIC NI8. The exchange / routing client 6 can also control the supply of video or audio data from other destination devices D2, D3, D9 via their associated ENIC NI9, NI10, NI11. The further exchange / routing client 61 can control a different subset of destination devices and the ENIC of these devices than the devices and ENIC controlled by the exchange / routing client 6.

  As described above, the network manager 4 maintains a database that identifies the current network configuration and works with the exchange / routing client 6 to set up the network. The network manager 4 can also allow the exchange / routing client 6 to send certain commands to the ENIC directly rather than to the ENIC via the network manager 4, but in many cases the network manager 4 All requests that may affect the configuration need to be sent through the network manager 4. Specific commands that do not affect the network and can therefore be sent directly from the exchange / routing client 6 to the ENIC include data stream control commands such as play, rewind, fast forward, etc. In addition to storing information identifying the network configuration, the network manager 4 allocates resources to the ENIC and exchange / routing clients 6, 61, which may affect audio and / or video data connections on the network. It has the function of controlling all certain commands and enabling the exchange / routing clients 6, 61 to correctly recognize the associated network connection.

Protocol and data flow (Figure 2)
In the Ethernet network configuration shown in FIG. 1, user datagram protocol (hereinafter referred to as UDP) / IP, transmission control protocol (hereinafter referred to as TCP), Internet group management protocol (Internet Group Management). Various well-known protocols including Protocol: hereinafter referred to as IGMP) can be executed. Other protocols executed in the network include the well-known real-time protocol (hereinafter referred to as RTP) and two protocols owned by Sony Corporation, Audio Video Switching Control Protocol (Audio Video Switching Control Protocol). Control Protocol: hereinafter referred to as AVSCP) and Client Network Manager Communication Protocol (hereinafter referred to as CNMCP). The AVCSP is used for connection control between the network manager 4 and the ENIC NI1 to NI11, and the CNMCP is used for communication between the network manager 4 and the exchange / routing clients 6 and 61. These protocols will be described in more detail with reference to FIG.

  FIG. 2 shows a part of the network shown in FIG. 1, where a network manager 4, an exchange / routing client 6 and a subset of ENIC, specifically NI1 (corresponding to the camera 1 of the source group). And NI2 (corresponding to both camera 1 and camera 2 in the source group) and NI8 (corresponding to video switch D8 in the destination group) are shown as examples. FIG. 2 is a diagram for explaining how the network manager 4, the exchange / routing client 6, and the ENIC NI1, NI2, and NI8 communicate with each other using a plurality of different communication protocols via the LAN. . As shown in FIG. 2, the network manager 4 communicates with the ENIC NI1, NI2, NI8 using AVSCP, while the exchange / routing client 6 communicates with the network manager 4 using CNMCP. The exchange / routing client 6 receives, as input signals, stream status (Stream Status: hereinafter referred to as SS) data for specifying the state of the control source group (CONTROL SOURCE GROUP) and AP proxy data P, and receives the unicode. Cast control data (Unicast Control Data: hereinafter referred to as UCD) is output to the network to control the source device or the destination device. In this configuration, all of ENIC NI1, NI2, and NI8 output proxy video P to the network, but only the exchange / routing client 6 receives the proxy video P as input data. The ENIC NI1, NI2, and NI8 output the proxy video P to the exchange / routing client 6 and / or the network manager 4 via the Ethernet switch 2, respectively, send and receive SS data via the LAN, and RTP communication data. , Output IGMP data specifying a multicast group to which the source device transmits data, and receive a UCD message. The ENIC NI 2 can directly transmit the UCD message to another ENIC NI 8, bypassing the network manager 4. As described above, direct communication between the ENICs is permitted only when the control command does not affect the network connection. Since ENIC NI8 corresponds to the destination group video switch D8, ENIC NI8 can send and receive SDI video streams, while ENIC NI1 and NI2 correspond to cameras, It simply receives the SDI video stream output from the camera, packetizes it, and sends it to the network.

AVSCP
AVSCP transmits the message using UDP (User Datagram Protocol). UDP is a connection restaurant sport protocol, which means that a transmitting device transmits a one-way data packet without notifying the receiving device that data is to be transmitted. Even if the receiving device receives each data packet, it does not return the status information to the transmitting device. This data format will be described later with reference to FIG. 3B in the “Data Format” chapter.

  AVSCP is used for connection control between the network manager 4 and each ENIC, and is used to manage the operating states of ENIC and AV (audio and video) ports. For example, when it is necessary to connect a video tape recorder (VTR) as a destination device to a camera as a source device and supply AV data, the exchange / routing client 6 corresponds to the destination device as a VTR in this specific example. It is necessary to instruct the input port of the ENIC to participate in the multicast group to which data is supplied from the camera. The instruction between the ENIC and the exchange / routing client 6 is performed using AVSCP.

The AVSCP protocol message has the following five main functions.
1) Monitor the operating state of ENIC.
2) Detect the configuration of ENIC.
3) Stop and start transmission of audio and video sources.
4) Instruct the ENIC and corresponding audio and video equipment to join the multicast group.
5) Establish and delete a path for transmitting control data over the network.

  The network manager 4 needs to know the operating state of the ENIC before sending an instruction to the ENIC. Therefore, in the AVSCP protocol, ENIC needs to periodically transmit a status message to the network manager 4. The network manager 4 can control transmission / reception of an AV stream to / from the ENIC only when the ENIC is in an operable state. Instead of obtaining network configuration information from messages periodically generated by the ENIC, the network manager 4 may send a configuration request message to the ENIC to actively detect the current ENIC configuration. In this case, the ENIC returns a message specifying the current configuration to the network manager 4 in response to this request.

  A specific example of the AVCSP message is shown below.

  STOP_TX and START_TX: By these, the network manager 4 can instruct the ENIC to stop transmission and start transmission of a specific AV data stream (specified by the AV input port of the ENIC).

  SWITCH_AV and SWITCH_AUDIO: These allow the network manager 4 to instruct the ENIC to add or delete an AV data stream or an audio data stream to a specific multicast group, respectively.

  SET_CTRL_TX and SET_CTRL_RX: These are messages for setting up the transmitting (TX) terminal and the receiving (RX) terminal of the AV data stream control path. When an application sends a SET_CTRL_TX message to the ENIC, this ENIC typically sends a SET_CTRL_RX message to the ENIC in the other terminal of the control path to establish a complete AV control path.

  UPDATE_TALLY: This is used to request the source / destination device corresponding to the ENIC port to update the display of collation text information. This command is often used when the AV source changes its display information.

  ACK: This is a message sent from the ENIC to the network manager 4 when the ENIC receives a command message from the network manager 4. The acknowledged command message is specified by the session ID value, and the response itself may be an affirmative response or a negative response. Since UDP is not a guaranteed delivery protocol, an AVSCP ACK message is required. If the response to the message is not within the predetermined time, the network manager 4 may repeatedly transmit the message for a predetermined maximum number of times.

  FIG. 14 shows how AVSCP relates to other functional modules in the ENIC network shown in FIG. The configuration shown in FIG. 14 shows the same protocol stacks 1100A, 1100B and the protocol stack 1120 of the network manager 4 in two different ENICs. The ENIC protocol stack includes an AVSCP layer 1104 provided above the UDP / IP / Ethernet layer 1102. Another protocol 1106 may be mounted on the same protocol stack level as the AVSCP layer 1104. The AVSCP layer 1104 communicates with the upper ENIC application layer 1108 using an AVSCP request command and an AVSCP instruction command. The top layer of the ENIC protocol stack 1100A represents the local configuration 1110 of the network. Similar to the ENIC protocol stacks 1100A and 1100B, the protocol stack 1120 of the network manager 4 includes an AVSCP layer 1124 provided above the UDP / IP / Ethernet layer 1122. The server application layer 1128 is provided above the AVSCP layer 1124, and communication between these two layers is arbitrated by an AVSCP request command and an AVSCP instruction command. The server application layer 1128 also communicates with an upper layer corresponding to the network configuration database 1130. The ENIC AVSCP layer 1104 can send AVSCP protocol messages to and receive messages from the corresponding AVSCP layer 1124 of the network manager 4.

  The AVSCP request is a primitive command sent from the ENIC application layer 1108 or the server application layer 1128 of the network manager 4 to the corresponding AVSCP layers 1104 and 1124. The application initiates an AVSCP request and sends AVSCP messages to other AVSCP entities. The AVSCP request includes parameters such as an IP address of a message destination (usually ENIC), an AVSCP type (for example, transmission stop, switching, etc.), and a plurality of information elements required by the message.

  One or more remote client controllers (not shown) may access the server application layer 1128 of the network manager 4 via a client controller interface (not shown). The client controller interface of the network manager 4 allows the client controller to remotely connect to the ENIC device and execute a set of control functions for the ENIC device.

  FIG. 15 shows the structure of the AVSCP header applied to all AVSCP messages. The AVSCP header has a fixed length of 32 bits. The first octet (bits 0 to 7) is used as a protocol identifier (protocol ID). This first octet has a value of 0xCC. The protocol ID is used to detect the possibility of collision with another protocol when another protocol uses the same port number. The second octet (bits 8-15) is used to indicate the protocol version number. The third octet (bits 16-23) is reserved for future use. The fourth octet (bits 24-31) indicates the message type. The last four octets of the AVSCP header are session IDs, which are random numbers selected by the command message sender, in order to link the original command message with the response message returned by the responder. Used.

CNMCP
As described above, the network manager 4 and the exchange / routing client 6 communicate with each other using CNMCP. CNMCP messages are transmitted using TCP (see the chapter “Data Format” and the data format of FIG. 3B). TCP is a connection-oriented protocol, which is used before transmitting data between network nodes. This means that the transmitting device and the receiving device need to cooperate to establish a two-way communication channel. For this reason, each data package transmitted over the local network receives an acknowledgment, and the sending device records status information to verify that each data package was received without error. To do.

  With the CNMCP, the exchange / routing client 6 can send a control message such as a registration request, a switching request or a permissions update to the network manager 4, and the network manager 4 can send a registration response to the exchange / routing client 6. Control messages such as a switching response, an update instruction (specifying the device configuration), and a permission response can be sent. By sending the CNMCP message to the exchange / routing client 6, the network manager 4 sends the data related to the ENIC connected to the network and the source device and destination connected to the network by this ENIC to the exchange / routing client 6. Data on the device can be notified. Further, by sending a CNMCP message from the network manager 4 to the exchange / routing client 6, the network manager 4 receives the proxy video stream, audio stream and status stream to the exchange / routing client 6. A multicast IP address that can be transmitted can be notified. The network manager 4 responds to the request from the exchange / routing client 6 to determine whether sufficient bandwidth is available to add a connection between the source device and the destination device, and to this determination In response, arbitrate access to network resources. The exchange / routing client 6 can also directly join the ENIC source / destination device to the multicast group without performing request access via the network manager 4. Such processing is appropriate only when, for example, the required connection data rate is low.

  Instead of CNMCP, for example, a simple network management protocol (Simple Network Management Protocol: hereinafter referred to as SNMP) may be used. The exchange / routing client 6 allows the network to transmit both audio and video streams from the source device specified by the exchange / routing client 6 to the destination device, and sends a CNMCP or SNMP message to the network manager 4. By doing so, the control data routing can be specified.

Audio and video data (RTP)
In order to transmit audio and video data streams from the source device to the destination device, the transport layer implements UDP multicast. Audio and video data are transmitted in a real-time protocol (hereinafter referred to as RTP) format by UDP packets. This format is applied to audio data, full-resolution video data, and low-resolution proxy video data (see the “Data Format” section, which will be described later, and FIG. 3A). RTP supports real-time traffic, that is, traffic that requires playback along the time axis in the destination application. Services provided by RTP are payload type identification (eg, video traffic), sequence numbering, time stamps and delivery monitoring. RTP supports data transfer to a plurality of destinations via multicast distribution if multicast distribution is supported by the underlying network. With the RTP sequence number, the receiving device can reconstruct the original packet sequence. Also, the correct position of the packet can be determined using the sequence number. RTP does not provide a mechanism to ensure timely delivery, nor does it make any other quality of service guarantees.

  When the ENIC receives an AVSCP switching request from the network manager 4, the ENIC sends an IGMP join message to the Ethernet switch 2 and joins the multicast group of data that needs to be received.

Unicast Control Data (UCD)
Control data can be sent directly from one ENIC to another ENIC only when transmitted as unicast transmission. If the control data can affect the virtual circuit switched connection in the network, the control data needs to be sent via the switching / routing client 6 and / or the network manager 4 to control the equipment. . Here, for a specific subset of control data, a controller connected to one ENIC may directly control a device connected to another ENIC, bypassing the network manager 4 and the exchange / routing client 6. it can. For example, commands such as play, pause, record, and jog may be sent directly from the controller to a source / destination group such as a VTR via the network. The control channel is established using AVSCP. The control data itself is transmitted as a UDP message in this embodiment. Instead of this, control data may be transmitted using TCP.

Stream status (SS)
Since the state data often has a narrow bandwidth, the exchange / routing client 6 can receive the state information SS without using the network manager 4 by using CNMCP. If the controller is connected to the network via the first ENIC and the controlled group is connected to the network via the second ENIC, the first ENIC needs to know the status of the controlled group. is there. For this purpose, the status data SS may be transmitted from the controlled group to the controller via the network. The exchange / routing client 6 can selectively receive the status data SS and monitor the current status of the data stream.

AV proxy stream (P)
The AV proxy stream is communicated over the network via UDP multicast using RTP. The switching / routing client 6 can selectively receive proxy video data for monitoring purposes and make informed switching decisions regarding virtual circuit switched connections. In the configuration shown in FIG. 2, only the exchange / routing client 6 receives the proxy video stream and is associated with ENIC NI1 (related to “Camera 1” S1 source group), NI2 (related to “Camera 2” S2 source group). ), NI8 (associated with the video switch D8 destination group) can output the proxy video data stream. Users of source group devices and destination group devices, such as cameras, VTRs, video processors, etc., often want to make editing decisions based on the content of audio and / or video data streams, and AV proxy streams are therefore Is generated. Some well-known video formats use RTP to transmit video data over a network, but these well-known techniques involve processing to highly compress the video data. Video compression processing in which a large delay period (eg, one field or more) is introduced is not suitable for a studio production environment to which the technology according to the present invention is applied. Furthermore, in a production environment, it may be necessary to display a plurality of AV data sources on the screen substantially simultaneously. In order to expand such a plurality of data streams, the burden on the data processor increases, You may need to strengthen your wear. Thus, in this embodiment, the video proxy is not a compressed data stream, but an uncompressed subsampled data stream (eg, QCIF (176 samples × 144 lines), 16-bit RGB, 25 frames per second, 15.2M with horizontal and vertical filtering. Bit sub-sampling per second).

Data format (Fig. 3A, Fig. 3B, Fig. 3C)
As shown in FIG. 3A, the audio video data format includes an Ethernet header, an IP multicast header, a UDP header, an RTP header, a field for specifying the type of payload, a payload, and cyclic redundancy. And a check (cyclic redundancy check: CRC) field. The Ethernet header stores a source Ethernet address and a destination multicast Ethernet address. The IP multicast header stores an ENIC IP address and a destination device multicast IP address. There are several different IP address classes for IP addresses. For example, in class A, 8 bits are assigned to the network ID, and the host ID is assigned to the subsequent 24 bits. In class B, the first 16 bits are assigned to the network ID, and the latter 16 bits are assigned to the host ID. Class D IP addresses are used for multicast transmission. The first 4 bits of the class D network address are always the binary pattern 1110, corresponding to decimal 224-239, and the remaining 28 bits are assigned to the multicast group ID. IGMP is used in connection with multicast transmission and class D IP addresses.

  A set of hosts (ie source and / or destination devices) corresponding to a particular IP multicast address is called a host group. A host group may include multiple networks within its scope, and members of the host group can be changed dynamically. Class D IP addresses are mapped to Ethernet addresses, and the last 23 bits of the multicast group ID (28 bits) are copied to the lower 23 bits of the Ethernet address. Therefore, 5 bits of the multicast group ID are not used for generating an Ethernet address. As a result, the mapping between the IP multicast address and the Ethernet address does not have a one-to-one relationship, that is, 32 different multicast group IDs are mapped to the same Ethernet address.

  The UDP header includes a source port number and a destination port number, which are usually associated with a particular application on the destination device. In the multicast message, since the multicast group address specifies the stream / content, the UDP is redundant in the case of the multicast message. The audio / video stream is transmitted using the RTP protocol. For example, forward error correction (hereinafter referred to as FEC) may be performed on a certain type of data stream such as a full-resolution video stream to perform a certain level of correction against data corruption due to a network error. . FEC is implemented using a known RTP payload format that provides FEC. FET is a parity-based error recovery technique.

  It is known that the video scanning line number can be specified in the RTP payload header by extending the RTP protocol. The RTP header further includes a field for specifying whether the video data is 8 bits or 10 bits. The well-known RTP and RTP / FEC protocol formats provide the necessary data packet fields for transmitting audio and video data over an IP network, but carry additional information such as source status and source time code information. It is desirable to be able to do so. For example, when the source device is a VTR, it is necessary to transmit a time code recorded on a tape-shaped recording medium via a network. The source status information indicates, for example, information such as whether or not the VTR is currently playing, stopped, or in jog / shuttle mode. With this status information, the user can operate the VTR from a remote network location. Since time code data and source state information need only be transmitted once per field, these information are transmitted in RTP packets marked as vertical blanking. In order to implement audio and video resynchronization, the RTP time code is based on a 27 MHz clock. The payload type field indicates the type of payload, that is, whether the payload is video data or audio data. The payload field contains video data or audio data to be transmitted. CRC is data for cyclic redundancy check well known in the art.

AVSCP and CNMCP
AVSCP and CNMCP messages are transmitted in a data format as shown in FIG. 3B. This format sequentially includes an Ethernet header, an IP header (not a multicast header), a UDP or TCP header, a payload, and a CRC field. The Ethernet header stores a source Ethernet address and a destination multicast Ethernet address. The IP header stores the IP address of the source ENIC and the IP address of the destination ENIC. UDP is used for AVSCP, and TCP is used for CNMCP. The payload field stores AVSCP or CNMCP message data. CRC is data for cyclic redundancy check well known in the art.

Stream Status Format The stream status (SS) format has the same structure as the audio and video data format shown in FIG. 3A, except for the contents of the payload section. This format has an Ethernet header, an IP multicast header, a UDP header, an RTP header, a payload type identification field, a stream status data payload, and a CRC field.

Unicast Control Data Format As shown in FIG. 3C, the unicast control data format has an Ethernet header, a standard IP header (not multicast), a UDP header, a payload section allocated to unicast control data, and a CRC field.

  IGMP is a well-known protocol. In multicast transmissions that extend beyond a single network, the Internet router needs to determine which hosts (in this case, source and destination devices) on a given physical network belong to the multicast group. Transmission is complex. IGMP is typically used to establish such information. IGMP informs all nodes on the physical network of the relationship between the current host and the multicast group. The IGMP message is transmitted in an IP datagram, and is generated by combining a 20-byte IP header with a fixed-length 8-byte IGMP message. The IGMP message includes a 32-bit class D IP address.

  A multicast router (eg, Ethernet switch 2 in FIG. 1) uses some IGMP queries and reports to determine which interface has at least one host (source / destination device or group) associated with the multicast group. Record. When the Ethernet switch 2 receives a multicast message from the source device, the Ethernet switch 2 transmits the message only to the interface having the destination device currently associated with the multicast group.

ENIC (Figure 4)
The ENIC joins the multicast group by sending an IGMP join message to the asynchronous Ethernet switch 2. The ENIC transmits and / or receives data in the audio / video format shown in FIG. 3A, the AVSCP / CNMCP format shown in FIG. 3B, or the UCD format shown in FIG. 3C. The ENIC does not transmit / receive CNMCP data (CNMCP data is transmitted / received only between the network manager 4 and the exchange / routing client 6).

  As shown in FIG. 4, the ENIC includes a network processor 20, a buffer / packet switch 22, a packetizer / depacketizer 24, a control processor (CPU) 26, and peripheral component interconnect: PCI) 28, clock 22, clock synchronization circuit 204, and frame synchronization circuit 205. The clock synchronization circuit 204 is disclosed in co-pending UK patent application No. 0204242.2. The frame synchronization circuit 205 is disclosed in UK patent application No. 030749.8, which is concurrently ongoing.

  The packetizer / depacketizer 24 comprises three video input terminals 218 for receiving individual SDI video streams and an audio input terminal 220 for receiving individual SDI audio streams. Alternatively, three input ports for receiving the combined SDI audio / video stream may be provided, and this audio / video stream may be separated into three audio streams and three video streams within the ENIC. . In a further variation, an AES digital audio stream may be provided as an input signal to the packetizer / depacketizer 24. Similarly, the packetizer / depacketizer 24 includes three video output terminals 222 and three audio output terminals 224.

  The CPU 26 includes three control data input terminals 226 and three control data output terminals 228, which provide control functions similar to those provided by the RS 422 in a conventional studio. ". The three video input terminals 218 are connected to three substantially real-time proxy video generators 212. The proxy video generator 212 generates a low resolution version of the video stream, as will be described later. Output signals from the proxy video generator 212 and the SDI video input terminal 218 are input to the packetizer / multiplexer 214, which supplies the full resolution serial signal supplied via the video input terminal 218. The video data and the proxy video from the proxy video generator 212 are converted into packets suitable for transmission over the network. The packet generated here is supplied to the buffer / packet switch 22. The packetizer / depacketizer 24 includes a depacketizer / demultiplexer 216 that receives packets representing SDI video and audio channel data from the buffer / packet switch 22. The depacketizer / demultiplexer 216 depackets and demultiplexes video and audio data into three serial video streams and three serial audio streams, which are then streamed into three video output terminals 222 and 3. This is supplied to each of the audio output terminals 224. In this way, the packetizer / depacketizer 24 receives video and audio data from the network in the packet format via the buffer / packet switch 22 and outputs them in the serial digital format via the output terminals 222 and 224. In addition to providing a routing function, it also provides a routing function that receives video and audio data in serial digital format from the input terminals 218 and 220 and supplies them to the buffer / packet switch 22 in a packet format for transmission over the network. . The packetizer / depacketizer 24 further includes a synchronization function for synchronizing different video and audio streams with a synchronization signal from the clock synchronization circuit 204, and video frames of different video streams according to the synchronization signal from the frame synchronization circuit 205. And a frame alignment function for aligning.

  The buffer / packet switch 22 routes video, audio, and control packets received from the network processor 20 based on a series of tags attached to the packets in the network processor 20. The network processor 20 generates a tag based on the header data of the received packet. The tag includes a “flow” tag that defines the route of the data through the buffer / packet switch 22 and the final output (in effect, for the data to be supplied by the packetizer / depacketizer 24). There are two types of tags that define “actions” to be executed. Video and audio packets are routed to the depacketizer / demultiplexer 216 and control packets are routed to the CPU 26.

  The network processor 20 includes a UDP / IP filter 208. The UDP / IP filter 208 uses the packet header information to receive synchronization packets, audio data packets, video data packets, status data packets, and control data packets received from the network. To detect. The network processor 20 supplies the received clock synchronization packet directly to the clock synchronization circuit 204 to synchronize the ENIC clock 202 to the master reference clock as disclosed in UK patent application No. 0204242.2. Further, the network processor 20 supplies the frame synchronization packet to the clock synchronization circuit 204, and then supplies it to the frame synchronization circuit 205 via the ENIC clock 202. The network processor 20 directly supplies the synchronization packet to the clock synchronization circuit 204 and the frame synchronization circuit 205, thereby reducing the time delay and increasing the synchronization accuracy. Other packets, such as AVSCP packets, are not recognized by the filter 208 and are supplied to the CPU 26 (however, as a modification, a filter for these may be provided). The network processor 20 tags the audio and video packets based on the header data received with the audio and video packets. The tagged audio and video packets are supplied to the buffer / packet switch 22, which supplies these packets to the inverse packetizer / demultiplexer 216 or the computer interface PCI 28. The control data packet with the tag attached is routed to the CPU 26 by the buffer / packet switch 22. The buffer / packet switch 22 will be described in detail later.

Data routing in ENIC
1. Data ENIC received from the network includes audio and video packets shown in FIG. 3A, AVSCP packets shown in FIG. 3B, stream status data packets (having basically the same format as shown in FIG. 3A), and unicode shown in FIG. 3C. A cast control data packet is received from the network. The Ethernet header provides the physical address of the ENIC, which allows the network to deliver the packet to the ENIC in a well-known manner.

  The ENIC network processor 20 (see FIG. 4) includes a UDP / IP filter 208, which extracts IP and UDP headers, decodes address information in the headers, and payload data from the payload type field. Are detected (see FIG. 3A). Next, the network processor 20 replaces the packet header with a tag identifier. The tag identifier specifies to which target data processing node, such as a video or audio processor, the packet payload data is routed via the ENIC. FIG. 5A shows the data format of a packet with a tag attached. The tagged data packet has a width of 32 bits and no data length is defined, that is, the payload has a variable length. The first 32 bits of the tagged data packet are composed of an 8-bit “flow” data field, an 8-bit “type” data field, and a 16-bit “size” field. The next 32 bits are not currently used. Following this unused field, a payload field is provided. For audio and video data, the tagged packet payload has an RTP header and payload type data in addition to the audio or video data payload shown in FIG. 3A. In the case of an AVSCP / CNMCP data packet and a control data packet (see FIGS. 3B and 3C), the packet payload with the tag attached is message data.

  The flow data field of the packet data with the tag shown in FIG. 5A defines the output terminal of the buffer / packet switch 22 (FIG. 4) corresponding to the target data processing node to which the payload of the packet with the tag is transmitted. To do. The type data field indicates what processing the target processor performs on the data, and the size data field indicates the payload size.

  FIG. 5B shows a specific example of flow assignment allocation. In this specific example, flow 0 corresponds to data that is not supplied to any target processing device, for example, data that is not tagged, and flows 1 and 4 are packetizer / depacketizer 24 (FIG. 4). ) For video input / output ports 218, 222, flows 2, 5 for CPU data flow to and from the network, and flows 3, 6 for PCI 28 data flow to and from the network. Corresponding to

  FIG. 5C shows how video data, PCI data, network data, and CPU data are mapped to six defined flow paths through a multiplexer (MUX) and a demultiplexer (DEMUX). Each data flow shown in FIG. 5B is associated with a FIFO. In this specific example, no direct means for determining the size or number of packets to be written to the FIFO is required, so such means are not provided. The tag associated with the packet specifies the packet size, so the MUX only needs information indicating that the FIFO is “not empty” in order to perform the read operation. The MUX module can be programmed to react only to specific flows (eg, by external means such as a CPU). Thereby, a virtual flow path can be constructed across the buffer / packet switch 22 shown in FIG. Similarly, to avoid collisions, a single DEMUX module can be programmed to support one data flow. Again, the mapping is programmably controlled by external means.

FIG. 6 shows a video processing unit of the packetizer / depacketizer 24. The video processing unit includes a demultiplexer 2401, and the demultiplexer 2401 responds to the “type” data in the tag attached to the video packet, and the three channels V ₀ , V ₁ , V indicated by this type data. ₂ is supplied with video packets. Each channel is provided with an RTP / FEC decoder and subsequent frame memories 2405, 2406, and 2407, respectively. The RTP decoder 2402 separates the tag from the received packet, writes the packet to the frame memory 2405 using the address defined by the RTP packet header, specifically its line number data, and the video data is arranged in the correct order. Generate a video frame.

First Specific Example of Operation: Multicasting of Audio Data In this specific example, it is desired to form a data communication path for transmitting AES audio data from the source group S9 to the audio processor D3 via the network. The AES audio data is packetized by the ENIC NI6, transmitted via the network, supplied to the ENIC NI10 and depacketized, and then supplied to the audio processor D3 in a serial digital format. The user can connect the audio source S9 and the audio processor D3 by interacting with a graphical user interface displayed by the exchange / routing client 6 and described later with reference to FIGS. In order to establish a communication path between the audio source S9 and the audio processor D3, the switching / routing client 6 sends a CNMCP switch request message to a predetermined port of the network manager 4 and the current configuration of the virtual circuit switched connection. Start changing. The network manager 4 transmits to the exchange / routing client 6 a CNMCP message that provides a source device and a destination device (and associated source group and destination group) to which the exchange / routing client 6 can connect. Thereby, the exchange / routing client 6 can know the current configuration and state of the network. Each source device and destination device has an associated ID assigned by the network manager 4, which is sent to the exchange / routing client 6, which exchanges with the subsequent network manager 4. This device ID is used in communication. In response to a request by the user to connect to S9 to D3, the exchange / routing client 6 transmits a CNMCP message including the ID of the related source device and the ID of the destination device to the network manager 4.

  If the exchange / routing client 6 is not authorized to perform this process (for example, if sufficient network bandwidth is not available to establish a reliable connection), the network manager 4 responds to the connection request. A negative acknowledgment (NACK) CNMCP message is sent to the exchange / routing client 6. On the other hand, when the network manager 4 permits connection establishment, the connection request is processed as follows.

  First, the network manager 4 makes an inquiry to the network configuration database and determines to which multicast IP address the AES audio data from the source group S9 is currently transmitted. Next, the network manager 4 generates an AVSCP exchange message including a multicast IP address to which the source group S9 transmits data, and transmits the AVSCP exchange message to the related port (device) of the ENIC NI 10 that connects the audio processor D3 to the network. The software incorporated in the ENIC NI 10 transmits an IGMP join message to the multicast IP address to which the audio data of S9 is transmitted, and returns an AVSCP ACK message to the network manager 4 to the network manager 4. As a result, the ENIC NI 10 receives the output signal from the audio source S9 in one of its destination devices, and routes this audio data to the source device (ENIC AES output port) connected to the audio processor D3. To do. On the other hand, the network manager 4 receives the AVSCP ACK message indicating that the instruction to participate in the specified multicast IP address has been permitted from the ENIC 10 and reflects the existence of a newly formed connection in the network configuration database. Update routing information in. Finally, the network manager 4 sends a CNMCP ACK message to the exchange / routing client 6 indicating that the requested audio data connection has been successfully established between S9 and D3.

Second Specific Example of Operation , Multicasting of AV Data In this specific example of operation, two source group devices shown in FIG. 1 are connected to a single destination group device. Specifically, output signals from “Camera 1” S1 and “Camera 2” S2 are supplied as input signals to the video switch D8. To initiate the connection between S1 and D8 and the connection between S2 and D8, the exchange / routing client 6 has ID values associated with "Camera 1" S1, "Camera 2" S2, video switch D8. Is sent to the network manager 4.

  As described above, the network configuration database of the network manager 4 also stores data related to each ENIC device category. Specifically, the network configuration database stores data indicating whether or not each source device is linked, the number of video lines delayed by the transmission of the data stream, the current transmission state of the source device, and the like. The network manager 4 further derives information about the destination device from the network configuration database, for example, information such as the IP address of the ENIC that realizes the device and the number of video lines delayed during playback.

The network manager 4 can determine a multicast IP address to which each of the camera source groups S1 and S2 should transmit data based on the network configuration database. Thereby, in order to establish a connection between the two cameras S1 and S2 and the video switch D8, the network manager 4 has a multicast IP address to which “Camera 1” S1 transmits AV data, and “Camera 2” S2 has An AVSCP message that specifies both the multicast IP address for transmitting AV data is transmitted to the ENIC NI8. Each AVCSP message from the network manager 4 is detected by the network processor 20 of the ENIC NI8 and supplied to the CPU 26 of the ENIC NI8, and the CPU 26 issues an IGMP join message to the network. The AV packet output by each of the two cameras S1, S2 is ENIC
Supplied to the network processor 20 of the NI8. The supplied video packet specifies the destination IP address in its header data, and the multicast group to which the AV packet is distributed is derived from the IP address. The ENIC NI 8 determines to which output port (source device) of the ENIC NI 8 the AV data that has been depacketized is routed from this multicast group. As described above, the multicast group defines to which subset of destination devices in the network the data packet is routed. In ENIC NI8, the network processor 20 separates the header from the AV packet (as described above using FIG. 4) and replaces it with a tag. The buffer / packet switch 22 routes the video packet to the demultiplexer 2401 (see FIG. 6A) based on the flow data in the tag. The demultiplexer 2401 de-packets this data and supplies it to the RTP / FEC decoders 2402, 2403 (shown illustratively), which decodes the de-packetized data to produce video Rebuild the frame. Data indicating video frames output from the RTP / FEC decoders 2402 and 2403 are supplied to frame memories 2405 and 2406, respectively. Further, the frame synchronization circuit 205 (see FIG. 4) of the ENIC NI8 aligns the frames of the two video streams in consideration of the line delay information stored in the network configuration database by the network manager 4. Video switch D8 (FIG. 1) receives two AV SDI streams from ENIC NI8.

  In addition to establishing a communication channel between "Camera 1", "Camera 2" and video switch D8, it is necessary to establish control channels identified as CONTROL_SOURCE data structure and CONTROL_DESTINATION data structure in the network configuration database. . The AV stream control path is established by sending two “CREATE_STREAM_CTRL” AVSCP messages from the exchange / routing client 6 to the two ENICs defining both ends of this control path. Each of the “CREATE_STREAM_CTRL” AVSCP messages defines one terminal on the control path in ENIC. When the control path is established, a UCD data packet can be transmitted to the ENIC NI8. For example, for the video switch D8, the output is changed from the data derived from “Camera 1” to the data derived from “Camera 2”. Can be instructed to change.

  Accordingly, the video switch D8 receives control data from the CPU 26 (FIG. 4) of the ENIC NI8 in addition to the AV data stream from “Camera 1” and “Camera 2”. The control data is transmitted as unicast control data by the exchange / routing client 6 (FIG. 1), and is supplied in a packet format to the network processor 20 (FIG. 4) of the ENIC NI 8 via the network. The unicast control data has a header indicating that the packet is a control packet, so these control packets are routed to the CPU 26 of the ENIC NI8 (as described with reference to FIG. 4). . With this control data, it is also possible to instruct the video switch D8 to switch its output signal from one AV stream to the other AV stream, for example, from “Camera 1” to “Camera 2”.

Third Specific Example of Operation: Propagation of Change of Collation Text Data via Network FIG. 7 is a block diagram showing a simplified specific example of the network configuration based on the present invention. This network includes two cameras “Camera 1” and “Camera 2”, a digital multi-effects (hereinafter referred to as DME) unit, an AB switch, and the current AB switch. A monitor capable of displaying an output AV stream of one of the two cameras according to the configuration. A network configuration is shown for ENIC associated with each of the network devices. That is, this network is connected to the ENIC_1 710 connected to the “Camera 1” source device, the ENIC_2 720 connected to the “Camera 2” source device, the ENIC_DME 730 connected to the DME unit, and the AB switch. ENIC_AB_SWITCH 740 and ENIC_AIR 750 connected to the monitor.

  ENIC_1 710 receives the SDI data output from “Camera 1”, packetizes this SDI data, and supplies it to the DME for digital multi-effect processing via the network and ENIC_DME 730. The SDI output data of the DME is returned to the ENIC_DME 730 and packetized, and supplied to the AB switch via the network and the ENIC_AB_SWITCH 740. The SDI data output from “Camera 2” is packetized by ENIC_2 720 and supplied to the AB switch via the network and ENIC_AB_SWITCH 740 in a packet format. Depending on the current configuration of the AB switch, the DME-processed output data of “Camera 1” or “Camera 2” is supplied to the ENIC_AIR 750, converted into the SDI format, and displayed on the monitor. The broken line between the ENICs in FIG. 7 represents the network connection from the ENIC, and the solid line represents the SDI connection to the ENIC. As described above, SDI data is supplied to the ENIC port and packetized and transmitted over the network to the destination device, while packet data from the network is received by the ENIC and depacketized, eg, SDI. It is supplied to the AV device as a serial digital data stream such as a data stream or an AES audio data stream.

  As described above, the network configuration data stored by the network manager 4 includes a “SOURCE” data structure, the “SOURCE” data structure includes a parameter “LINK”, and the source of LINK = 1 is data from the destination device. Is the source supplied. The video source device corresponding to each camera has a value of LINK = 0 and is therefore a “pure” source, ie they directly generate the data to be output. Each camera has a user group called “Producer”, and the producer sets collation text that is the name of the photographer. For example, “Camera 1” is “FRED”, “Camera 2”. "Is set as" Jim "(JIM). ENIC_1 710 is associated with “Camera 1”, ENIC_2 720 is associated with “Camera 2”, and the other three ENICs on the network are ENIC_DME 730, ENIC_AB_SWITCH 740, and ENIC_AIR 750. The ENIC_DME 730 performs digital multi-effect (DME) processing on the video data from the “camera 1”. The ENIC_DME 730 has two device entries stored in the network configuration database by the network manager 4, and these device entries are labeled “DME In” and “DME Out”. “DME In” is a destination device that receives packet data from “Camera 1” via the network and supplies it to the DME unit, and has a video link to the source device “DME Out” on the same ENIC. Packet data supplied from “Camera 1” and subjected to DME processing is transmitted to the ENIC_AB_SWITCH 740 via the source device “DME Out”. Furthermore, “DME Out” has a collation text of E1 (indicating EFFECT1). ENIC_AB_SWITCH 740 performs seamless switching between the “DME Out” source device and the source device associated with ENIC — 2 720 that outputs data from “Camera 2”. This ENIC_AB_SWITCH 740 has three device entries labeled “Switch A In”, “Switch B In”, and “Switch Out” in the network configuration database. “Switch Out” is either “Switch A In” or “Switch B In” (ie, the processed AV stream from “Camera 1” or the AV from “Camera 2”, depending on which video source is selected. Source device linked to a stream). ENIC_AIR 750 has one device that is the destination device labeled “Monitor” (monitor with collation display). “Monitor” is a “pure” destination device (LINK = 0) because it does not supply data to other source devices. The “Monitor” device receives video data from the AB switch via the ENIC_AB_SWITCH 740 and has matching text that displays metadata from the source device that is the “Switch Out” source device of the ENIC_AB_SWITCH 740.

  Here, how the change of the collation text data of the source device is propagated to the final destination device via the network connection according to the present invention will be described. For example, assume that the AB switch indicates channel A and the metadata of the camera 1 is changed. If the collation text entry for “Camera 1” has been changed from “Fred” to “Rob” in response to the current cameraman change, ENIC_1 710 tells Network Manager 4 that it is associated with the “Camera 1” source device. The collation text data to be changed is requested to be changed from “Fred” to “Rob”. The network manager 4 makes an inquiry to the network configuration database and checks each destination device participating in the multicast group to which the camera 1 source data is supplied. The network manager 4 updates the information of all clients that display the collation text data of the ENIC_1 source device. If any of these destination devices is a linked device (ie, a device that supplies received data to a further source device), that device navigates to the corresponding linked source device. , Update all the destination devices. In the configuration shown in FIG. 7, the destination device “DME In” of the ENIC_DME 730 is linked to the source device “DME Out” on the same ENIC (ie, linked to a different port on the same ENIC). The collation text (E1) of the source device “DME Out” is combined with “Rob” to become ROB_E1, and it is necessary to notify this change to all the destination devices currently receiving data from “DME Out”. The only destination device for ENIC_AB_SWITCH 740 is “Switch A In”. The switch is currently set to receive data from channel A (ie from camera 1), since “Switch A In” supplies data to the “Switch Out” source device of ENIC_AB_SWITCH 740 (which is the same ENIC). , “Switch A In” (not “Switch B In”) is now linked to the destination device, and all destination devices in “Switch Out” are updated. In this specific example, “Switch Out” has only one destination device that is “Monitor” on ENIC_AIR 750, which is a pure destination device. Therefore, the collation text of “Monitor” is updated to “ROB_E1” (in place of “FRED_E1”). In this way, matching text changes are propagated effectively to the relevant nodes of the network.

  Next, execution of AB switching for displaying the output data of “camera 2” instead of the output data of “camera 1” displayed on the monitor will be described. In this case, a request for executing seamless AB switching between the destination devices “Switch A In” and “Switch B In” on the ENIC_AB_SWITCH 740 is transmitted to the network manager 4. The network manager 4 consults the network configuration database to determine the current state of the ENIC associated with the requested switch, and if the network is correctly configured, the network manager 4 performs a switch between the two source devices. Start the virtual circuit switched connection change necessary to The source device on ENIC_2 720 that supplies data to “Switch B In” on ENIC_AB_SWITCH 740 is associated with “Camera 2”. The network manager 4 can access the “camera 2” using the network configuration database and update the state to “ON AIR *”. Similarly, if the AB switch configuration is changed to reactivate the connection to “Switch A In”, the device is accessed from “Switch A In” and “Camera 1” is set to “OFF AIR (* OFF AIR). *) ". The matching text associated with “Camera 2”, ie, the correct matching text that is “JIM” is propagated to “Monitor” as described above, and is currently displayed as “FRED_E1” or “ROB_E1” related to “Camera 1”. The matching text being replaced is “JIM”.

Data transmission to the network (Fig. 6B, Fig. 6C)
As shown in FIG. 6B, data is supplied to a buffer 2408 from an SDI source such as a camera via one channel of SDI video. The buffer 2408 temporarily buffers video data. The video data is packetized by the RTP / FEC encoder 2410 and then supplied to the buffer 2412 to be temporarily buffered. The tag generator 2414 adds a tag including the flow data and type data shown in FIGS. 5A and 5B to the RTP packet. Multiplexer 2416 receives the tagged packet from tag generator 2414 and multiplexes this video packet with video packets from other similar video channels. The tag is defined by data generated by the CPU 26 in accordance with the AVSCP message received from the network manager 4. As shown in FIG. 5C, the packet switch routes the video packet to the network processor (net) or PCI 28 based on the flow data in the tag. Audio packets are similarly processed and routed.

  When routing a packet to the network, the header generator 210 (FIG. 4) separates the tag from the packet and generates an appropriate portion of the network header attached to the packet based on the flow flag and type flag.

Proxy Video Referring to FIG. 8, the proxy video is generated from the SDI video as follows. The horizontal filter 70 is a low-pass FIR filter for SDI input data. The data filtered by the horizontal filter 70 is supplied to the horizontal subsampler 71. The horizontal subsampler 71 subsamples the SDI video in the horizontal direction, that is, reduces the horizontal resolution. The vertical subsampler 72 subsamples the data received from the horizontal subsampler 71 in the vertical direction to reduce the vertical resolution. The proxy video generated in this way is encoded by the encoder 74 to generate an RTP packet. There is one proxy video generator for each video channel. The proxy video is processed in the packetizer / depacketizer 24, the buffer / packet switch 22, and the network processor 20 in the same manner as the SDI video. Proxy video is always supplied to the exchange / routing client 6 or to either the exchange / routing client 6,61. Thereby, one proxy video stream is multicast to the first multicast group in which the exchange / routing client 6 and / or the exchange / routing client 61 participates, and the SDI video (the SDI video that is the origin of the proxy video) is Multicast to the second multicast group. A multicast group is defined by a class D IP address that identifies a data stream. As a variant, proxy video streams or high-resolution SDI video streams may be assigned to different multicast groups.

  In the presently most preferred embodiment of the present invention, proxy video is generated with horizontal and vertical filtering at 180 samples × 144 lines (PAL) or 180 samples × 120 lines (NTSC) and 25 or 30 frames per second. The number of bits per sample may be 24 bits (ie, each of the three primary colors is represented by 8 bits) or 16 bits (ie, each of the three primary colors is represented by 5 bits).

Exchange / routing client 6
9 and 10 show specific examples of a graphical user interface (graphical user interface: hereinafter referred to as GUR). In this specific example, the GUI is provided by the exchange / routing client 6, which may be a personal computer with a monitor, a keyboard and a mouse. The GUI may be provided by the network manager 4 or may be provided by both the network manager 4 and the exchange / routing client 6. The GUI manages an interface with underlying software that responds to operations (eg, mouse clicks or keyboard input) performed by a user using the GUI.

The data flow GUI provides information regarding the configuration of the network provided by the network manager 4. This information is provided using the CNMCP protocol as described above. The GUI also displays proxy video provided by ENIC using Real Time Transfer Protocol (RTP) as described above. The proxy video is multicast over the network via the ENIC from the source group that generates the proxy video and is received by the exchange / routing client 6 participating in the multicast group of the proxy video stream. This data routing is performed using an IGMP message command. Using this GUI, it is also possible to control a controllable source group such as a VTR or a destination group such as a video processor. The exchange / routing client 6 can directly unicast control data to the ENIC associated with the control source group in response to operations performed via the GUI. The unicast of the control data is as described above. As described above, the exchange / routing client 6 receives the state stream data when participating in the multicast group to which the state stream data is transmitted.

  When the GUI is used for routing video from the source device to the destination device, a CNMCP message is transmitted to the network manager 4. The network manager 4 transmits an AVSCP message to the ENIC related to the destination device, and joins the destination device to the requested multicast group.

  The exchange / routing client 6 can send an IGMP join message to the network. Note that the exchange / routing client 6 may voluntarily subscribe to a multicast group of only status, audio, and proxy data streams (self-subscribe). The network manager 4 controls client access to the multicast group corresponding to the video stream.

GUI
In the following description, it is assumed that the GUI is operated by a known technique using at least one input device such as a mouse and / or a keyboard. Alternatively, the command may be issued using a keyboard interface or touch screen interface having a “hot key” mapped to a specific GUI command. The GUI shown in FIG. 9 has three main display areas A1, A2, and A3.

  The area A1 is a network-related area that displays a graphic representation of a group (for example, the camera CAM1 and the like and the video tape recorder VTR1 and the like) and its source device (for example, the output CAM V1 of the CAM1). The graphical representation of the group is displayed with matching text (eg, CAM1) and the source device is displayed with its sub-matching text (eg, CAM V1). Data for generating the display content of the area A1 is derived from a database managed by the network manager 4 and provided to the exchange / routing client 6 using a CNMCP message.

  The area A2 is a source client review area and has a plurality of proxy video display areas or windows W1 to W10. In this example, 10 windows are shown, but this number can be any suitable number. Windows W1-W10 display proxy video. In this specific example, the proxy video displayed in the window is selected by dragging the source device from the network management area A1 and dropping it on the desired window. Further, the display window also displays identification information indicating the source group associated with the currently displayed proxy video. Due to the drag and drop operation, the underlying software sends an IGMP join message to the network and joins the exchange / routing client 6 to the multicast group in which the proxy video associated with the selected source device is currently being transmitted.

  Windows W1-W10 include regions L1-L10 labeled with a GUI that displays appropriate collation text and / or sub-collation text associated with the source device.

  Area A3 is a routing review area including button B that functions as an operator. In this specific example, two rows of buttons are provided. One row of buttons is associated with the source group and / or source device, labeled with the appropriate matching text corresponding to the source, and the other row of buttons is the button corresponding to the destination device. Yes, a matching text corresponding to the corresponding destination device is attached as a label. The user can select a source button or one or more destination buttons in the GUI area A3 (for example, by a mouse click operation, a keyboard input operation, or a touch operation on an appropriate area in the touch screen interface). The communication path is established such that the source corresponding to the selected source button is linked to the selected destination over the network. In the specific example shown in FIG. 9, CAM1 corresponding to the highlighted button is linked to MON1, VTR2, DSP2, and audio data related to CAM1 is linked to AU OUT3.

  Here, it is further assumed that the source CAM1 is connected to MON1. When the exchange / routing client 6 is started up, the exchange / routing client 6 connects to the network manager 4 via the known port 4, and the network manager 4 provides information about the source equipment that the exchange / routing client 6 can use. To do. Thereby, the exchange / routing client 6 can know the configuration of the network. This network configuration is reflected in the GUI display, so that the user can also know the network configuration. Information about each device is provided to the exchange / routing client 6 along with the ID, and the exchange / routing client 6 describes the device using this ID in subsequent communication with the network manager 4. The destination device may be a monitor, for example. If the exchange / routing client 6 wants to route video data from a source group (eg, VTR), the exchange / routing client 6 will send a CNMCP switch message to the network manager 4 containing the destination device and source device IDs. Send.

  If the exchange / routing client 6 is not authorized to perform such processing, the network manager 4 returns a CNMCP NAK message to the client. In other cases, the network manager 4 processes this request as follows.

  The network manager 4 checks the network configuration database and determines to which multicast IP address the video data is transmitted. Next, an AVSCP switching message including the IP address is generated and transmitted to the ENIC connected to the monitor. The software installed in the ENIC sends an IGMP join message to this IP address and returns an AVCSP ACK message to the network manager 4. This allows the ENIC to receive the desired video data and supply this data to the SDI port connected to the monitor. On the other hand, the network manager 4 receives the AVSCP ACK message and updates the routing information in the database. The network manager 4 returns a CNMCP ACK message to the client, notifying that the processing has been successful.

  The GUI preferably has two further display areas M1, M2 as shown in FIG. 9 showing the video displayed on the play-out monitors MON1, MON2. In this specific example, MON2 has a dark border, which indicates that video data is reproduced and output from VTR1 to LINE OUT1, for example. MON2 has a bright border, which indicates that the video data from CAM1 is reserved for the next playback output. The video to be displayed can be selected by dragging and dropping the proxy video from the windows W1 to W10 to MON1 and MON2. Further, by clicking MON1 or MON2, video data to be reproduced and output may be selected or switched.

  The GUI shown in FIG. 9 has an audio control display area AVD.

  Further, the GUI includes virtual user operators C1 to C10 associated with the windows W1 to W10 and user operators CM associated with MON1 and MON2. When the user operates these user controls, the underlying software directly transmits the unicast control data UCD to the source group that is the output source of the video data displayed in the related window via the network. Alternatively or additionally, the virtual user controls C1 to C10 can also indicate the current state of the associated device.

  FIG. 10 shows a GUI obtained by slightly modifying the GUI shown in FIG. This GUI includes proxy video display areas W1 to W8, a network management area A1 (shown only schematically) similar to FIG. 9, and monitor displays “M1” and “M2” in the area A5. . The GUI shown in FIG. 10 does not have a row of source buttons and destination buttons corresponding to the area A3 in FIG. 9, but instead of this, two buttons M1, which function as switches like the buttons in FIG. Has M2. The video currently being played back is displayed in the playout window P0.

  The windows “M1” and “M2” are associated with audio operators A1 and A2 for switching on / off of the audio monitor, whereby the user monitors the audio related to the images in the windows M1 and M2. can do.

  The video displayed in the windows M1 and M2 can be selected by dragging and dropping the video from the proxy video windows W1 to W8 to the windows M1 and M2. By such a drag-and-drop operation, a full-resolution video signal (not a proxy video) is supplied from the source to a full-resolution monitor such as MON1, MON2, etc. shown in FIG. 1, and in FIG. 1 via ENIC NI8. Is supplied to a video switch such as D8. In this way, the reduced bandwidth proxy video allows the user to select what virtual circuit switched connection to establish in the network, and for each proxy video source stored by the network manager 4 The data associated with the full-resolution video stream from which the proxy video is derived can establish a data communication path in response to a GUI event performed by the user. Each source group in which the proxy video stream is generated is associated with at least two multicast IP addresses, one IP address is a multicast IP address to which full resolution video data is transmitted, and the other IP address is A multicast IP address to which low-resolution proxy video data is transmitted. By operating the buttons M1, M2, the underlying software supplies the unicast control data UCD to the video switch via the ENIC NI8, which causes the video switch to switch between two different data sources.

  FIG. 11 shows a GUI that provides operators with an overview of the network configuration. This GUI has a first source panel 110 showing active and inactive sources belonging to the IP network. Here, for example, source groups such as cameras CAM1, CAM2, and CAM3 are displayed. The video tape recorder group VTR1 has independent audio VTR A1 / 2, VTR A3 / 4, and video VTR V1 equipment (that is, different input / output terminals) corresponding to VTR V1, and these are also displayed. On the first source panel 110, for example, the MIC 1 corresponding to the first microphone, the source name MIN A1 / 2 specifying the audio channel device, and the like are also displayed. The source type is displayed by an icon, but the source name is not displayed by the icon. The input can be selected by highlighting the desired source on the first source panel 110, for example, in this example, the current camera 1 (CAM1) is selected. The network review panel 112 has three subpanels: a control subpanel 114, a source subpanel 116, and a destination subpanel 118. The connection between the controller, source and one or more destinations is represented by a color-coded branch connection between entries in these three subpanels. In the current configuration shown here, the first controller CONT1 controls the source group CAM1, which includes two monitors MON1, MON2, video cassette recorder VTR1, audio output AUDIO OUT3, digital Data is provided to six different destination devices of the signal processor DSP2 and the output line LIN OUT1. The source sub-panel 116 displays a pull-down menu for each source that provides more detailed information about the device, such as audio and video data streams associated with that source. The relationship between the source and the digital signal processor (DSP) is indicated by a color code in the left margin of the source sub-panel 116, for example, in this example, CAM1 is associated with DSP2 and DSP3. The names of sources such as CAM1, VTR1, MIC1, etc. are derived from the collation text. The GUI shown in FIG. 11 can also display status information (for example, on-air / off-air) related to the source device or destination device in the network. Such status information is supplied to the network as a status packet by the corresponding device. The network manager 4 collates the state data in the network configuration database, and the GUI expression is periodically updated based on the updated information in the database.

  FIG. 12 shows an example of a GUI that displays a connection between a source and a destination via a network. An area 121 indicates a group (for example, CAM1) and related source devices (for example, V1, V2), and an area 122 indicates a destination. Each source group has a colored bar 124 associated with the source group. Area 121 shows the connection between the source and destination using a colored bar. The GUI shown in FIG. 12 provides an interface that provides the user with an overview of the network and displays to the operator how data is being routed through the network. This GUI has a routing review overview panel 121 provided at the top of the screen, and a main routing review panel 122 including a source sub-panel 123 and a destination sub-panel 124. The routing review overview panel 121 makes it possible to easily grasp the relationship between the source and the destination. This is realized by emphasis with a color code. This routing review overview panel 121 indicates that CAM1 is currently connected to destinations MON1, MON2, MON3, VTR2, and AU OUT3. By clicking on a given source area of the routing review overview panel 121, that source and all destinations associated with it are highlighted. The source sub-panel 123 displays the source in more detail. Here, a source group such as CAM1 and a related destination device V1 or V2 are visually displayed. Similarly, the destination sub-panel 124 displays the destination in more detail. From the highlighted areas in the source sub-panel 123 and the destination sub-panel 124, for example, it can be seen that the CAM1 device V1 is connected to V1 and V2 of MON1. The destination subpanel 124 also provides a visual color code matrix representation of the source-destination connection.

  In the network configuration having the GUI shown in the specific examples of FIGS. 9 to 11, the user can confirm the complete configuration of the network based on all the data in the network configuration database stored by the network manager 4. . Here, in a variant, the network manager 4 stores a user-specific profile in which each user relates to a part of the network configuration that can be verified and in connection with the establishment and deletion of virtual circuit switched connections. Assigned to a specific permission level. The access permission level indicated by the user-specific profile may be determined by the user's job title (eg, photographer, editor, director, producer), or may be determined for each unique ID associated with an individual user. This gives, for example, a director with access rights that can check the current configuration of the entire network, but cannot change the virtual circuit switched connection, while a cameraman has some cameras operated by that cameraman. It is possible to perform setting such as giving an access right to confirm and change the configuration or subset of the included network.

  FIG. 13 shows a user interface provided by the network manager 4 that allows the user to manually enter configuration data. When the device is connected to the network, the user informs the network manager 4 via this user interface. The interface has an ENIC ID dialog box, a port ID dialog box, and a matching text dialog box. The user inputs information necessary for the network manager 4 to determine the network configuration in these dialog boxes. For example, an identifier defined by a user such as ENIC 6 is input to the ENIC ID dialog box, information specifying the ENIC port to which the device is connected is input to the port ID dialog box, and the collation text dialog box is A freely assigned label (referred to as matching text in the embodiment described herein) is entered that is used as the source / destination identifier. In addition to (and instead of) the source and destination identification IDs described above, a collation text ID may be used.

It is a block diagram which shows the structure of the network in a studio. It is a figure which shows the data flow through a network roughly. A is a diagram showing a format of an audio or video packet used in the network, B is a diagram showing a format of an AVSCP or CNMCP packet used in the network, and C is a diagram showing a unicast data packet. It is a block diagram which shows the structure of the network interface of the network shown in FIG. It is a figure which shows the format of the data packet used in a network interface. It is a figure which shows the specific example of flow allocation. It is a figure which shows the specific example of the data flow in ENIC. A is a diagram showing a packetizing switch in a network interface, and B is a diagram showing a depacketizing switch in a network interface. FIG. 2 is a block diagram illustrating an exemplary small network that describes a mode of operation of the network. It is a block diagram which shows the structure of the proxy generator of a network interface. It is a figure which shows an example of a graphical user interface. It is a figure which shows the other example of a graphical user interface. It is a figure which shows an example of the graphical user interface which shows the structure of a network. FIG. 3 is a diagram illustrating an example of a graphical user interface that displays how data is routed over a network. It is a figure which shows the user interface provided in the network manager where a user inputs configuration data. It is a figure which shows a protocol stack. It is a figure which shows an AVSCP header.

Claims (26)

A plurality of video sources for sending high-resolution video data and low-resolution video data having a lower resolution than the high-resolution video data to a network;
At least one destination device for processing video data received via the network;
A network switch for selectively routing data from the video source to the destination device;
A network control device connected to the network switch,
The network controller displays the display device and the low resolution video data from at least a subset of the plurality of video sources, together with identification information associating the low resolution video data with each video source, on the display device. A graphical user interface (GUI), user selection means for the user to select a video source of the high resolution video data and a corresponding destination device using the graphical user interface, and from the selected video source, A video network comprising: control means for controlling routing of high-resolution video data to the selected destination device.   The video network according to claim 1, wherein the network control device includes a personal computer.   3. The video network according to claim 1, wherein the display device displays a plurality of display areas each displaying low resolution video data from each video source together with associated identification information.   4. The graphical user interface provides a switch operable by one or more users specified by identification information for selecting a destination device connected to a selected video source. A video network according to claim 1.   5. The network control device according to claim 4, further comprising a user input device for selecting a display screen area, wherein the switch operable by the user is a display screen region selectable by the user input device. Video network.   5. The video network according to claim 4, wherein the display screen is a display screen with a touch sensor, and the switch operable by the user is a display screen area that can be selected by touching the user.   5. The video network according to claim 4, wherein the network control device includes a plurality of buttons operable by a user corresponding to a video source and / or destination device to be selected.   The graphical user interface provides at least one selection display area, and a video source is selected by dragging and dropping a displayed representation corresponding to the video source to be connected to the destination device into the selection display area. 5. A video network according to claim 4, wherein:   9. The video network according to claim 1, wherein the video network is a packet-based network in which the video sources are associated with different multicast groups.   The video sources are each associated with at least two multicast groups associated with the high resolution video data from the video source and the other with the low resolution video data from the video source. The video network according to claim 9.   The network controller routes a route from the selected video source to the selected destination device by sending a message to the destination device so that the destination device joins the multicast group of the selected video source. 11. The video network according to claim 9, wherein the video network is controlled.   The video network according to claim 1, comprising a plurality of destination devices.   13. The video network according to claim 1, wherein the at least one destination device includes a video switching device.   14. The video network according to claim 1, wherein the at least one destination device includes a video display device.   15. The video network according to claim 1, wherein at least one of the plurality of video sources includes a video tape recorder.   16. The video network according to claim 1, wherein at least one of the plurality of video sources includes a video camera. At least one of the video source and / or destination device sends a status packet providing device status information to the network;
The video network according to any one of claims 1 to 16, wherein the graphical user interface displays the status information in association with a representation of a corresponding device. The graphical user interface provides a user operator for controlling at least one operation of the video source and / or destination device;
The video network according to claim 1, wherein the network control device transmits a control packet for providing control information to the video source and / or destination device.   19. A video network according to any one of the preceding claims, wherein the network controller provides access to different subsets of representation and / or control functions for different users of the network. A plurality of video sources for sending high-resolution video data and low-resolution video data having a lower resolution than the high-resolution video data to a network, and at least one destination device for processing the video data received via the network And a video network control device used in a video network comprising a network switch connected to the video network control device and selectively routing data from the video source to the destination device,
A graphical user interface (GUI) for displaying the low resolution video data from at least a subset of the plurality of video sources on a display device with identification information associating the low resolution video data with each video source;
User selection means for the user to select a video source of the high resolution video data and a corresponding destination device using the graphical user interface;
A video network control device comprising: control means for controlling routing of the high-resolution video data from the selected video source to the selected destination device.   The video network control device according to claim 20, further comprising a display device. A plurality of video sources for sending high-resolution video data and low-resolution video data having a lower resolution than the high-resolution video data to a network, and at least one destination device for processing the video data received via the network And a network switch connected to the video network control device and selectively routing data from the video source to the destination device.
Displaying the low resolution video data from at least a subset of the plurality of video sources on a display device, with identifying information associating the low resolution video data with each video source;
Providing a user option for a user to select a video source of the high resolution video data and a corresponding destination device;
And controlling the routing of the high resolution video data from the selected video source to the selected destination device.   Computer software comprising program code for executing a method of operating a video network control device according to claim 22.   24. A providing medium for providing computer software according to claim 23.   The medium according to claim 24, wherein the medium is a recording medium.   25. The providing medium according to claim 24, wherein the providing medium is a transmission medium.

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